5 research outputs found
Plant communities as a tool in temporary ponds conservation in SW Portugal
Pond conservationTemporary ponds are seasonal wetlands
annually subjected to extreme and unstable ecological
conditions, neither truly aquatic nor truly terrestrial.
This habitat and its flora have been poorly
studied and documented because of the ephemeral
character of the flora, the changeable annual weather
that has a great effect on the small, herbaceous taxa
and the declining abundance of temporary ponds. The
objectives of this study are: (a) to define plant
community diversity in terms of floristic composition of ephemeral wetlands in SW Portugal, (b) to identify
temporary pond types according to their vegetation
composition and (c) to identify those ponds that
configure the European community priority habitat
(3170* – Mediterranean temporary ponds).
Vegetation sampling was conducted in 29 ponds,
identifying 168 species grouped among 15 plant
communities. Soil texture, pH, organic C and N
content were measured, but only N and percent of
clay appear to be related with the distribution of each
community type. The results showed that ephemeral
wetlands could be classified into four type: vernal
pools, marshlands, deep ponds and disturbed wetlands.
Vernal pools correspond to the Mediterranean
temporary ponds (3170*), protected as priority habitat
under the EU Habitats Directive. Submersed
Isoetes species (Isoetes setaceum and Isoetes velatum)
represents, together with Eryngium corniculatum,
the indicator species for vernal pools. We
identify also indicator plant communities of this
priority habitat, namely I. setaceum and E. corniculatum–
Baldellia ranunculoides plant communities. In
this region, the conservation of temporary ponds has
so far been compatible with traditional agricultural
activities, but today these ponds are endangered by
the intensification of agriculture and the loss of
traditional land use practices and by the development
of touris
Basin characteristics and nutrient losses: The EUROHARP catchment network perspective
The EC-funded EUROHARP project studies the harmonisation of modelling tools to quantify nutrient losses from diffuse sources. This paper describes a set of study areas used in the project from geographical conditions, to land use and land management, geological and hydro-geological perspectives. The status of data availability throughout Europe in relation to the modelling requirements is presented. The relationships between the catchment characteristics and the nutrient export are investigated, using simple data available for all the catchments. In addition, this study also analyses the hydrological representativity of the time series utilised in the EUROHARP project